[PATCH 1/7] cifs: change_conf needs to be called for session setup

[PATCH 1/7] cifs: change_conf needs to be called for session setup

[nspmangalore]

From: Shyam Prasad N <sprasad@microsoft.com>

Today we skip calling change_conf for negotiates and session setup
requests. This can be a problem for mchan as the immediate next call
after session setup could be due to an I/O that is made on the
mount point. For single channel, this is not a problem as
there will be several calls after setting up session.

This change enforces calling change_conf for the last session setup
response, so that echoes and oplocks are not disabled before the
first request to the server. So if that first request is an open,
it does not need to disable requesting leases.

Cc: <stable@vger.kernel.org>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
---
 fs/smb/client/smb2ops.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/fs/smb/client/smb2ops.c b/fs/smb/client/smb2ops.c
index 509fcea28a429..3625030d1912f 100644
--- a/fs/smb/client/smb2ops.c
+++ b/fs/smb/client/smb2ops.c
@@ -111,10 +111,19 @@ smb2_add_credits(struct TCP_Server_Info *server,
 				      cifs_trace_rw_credits_zero_in_flight);
 	}
 	server->in_flight--;
+
+	/*
+	 * Rebalance credits when an op drains in_flight. For session setup,
+	 * do this only when the server actually granted positive credits (>2) so a
+	 * newly established secondary channel can reserve echo/oplock credits.
+	 */
 	if (server->in_flight == 0 &&
 	   ((optype & CIFS_OP_MASK) != CIFS_NEG_OP) &&
 	   ((optype & CIFS_OP_MASK) != CIFS_SESS_OP))
 		rc = change_conf(server);
+	else if (server->in_flight == 0 &&
+		 ((optype & CIFS_OP_MASK) == CIFS_SESS_OP) && add > 2)
+		rc = change_conf(server);
 	/*
 	 * Sometimes server returns 0 credits on oplock break ack - we need to
 	 * rebalance credits in this case.
-- 
2.43.0

[PATCH 2/7] cifs: abort open_cached_dir if we don't request leases

[nspmangalore]

From: Shyam Prasad N <sprasad@microsoft.com>

It is possible that SMB2_open_init may not set lease context based
on the requested oplock level. This can happen when leases have been
temporarily or permanently disabled. When this happens, we will have
open_cached_dir making an open without lease context and the response
will anyway be rejected by open_cached_dir (thereby forcing a close to
discard this open). That's unnecessary two round-trips to the server.

This change adds a check before making the open request to the server
to make sure that SMB2_open_init did add the expected lease context
to the open in open_cached_dir.

Cc: <stable@vger.kernel.org>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
---
 fs/smb/client/cached_dir.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/fs/smb/client/cached_dir.c b/fs/smb/client/cached_dir.c
index 04bb95091f498..e9917e5204b00 100644
--- a/fs/smb/client/cached_dir.c
+++ b/fs/smb/client/cached_dir.c
@@ -286,6 +286,13 @@ int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon,
 			    &rqst[0], &oplock, &oparms, utf16_path);
 	if (rc)
 		goto oshr_free;
+
+	if (oplock != SMB2_OPLOCK_LEVEL_II) {
+		rc = -EINVAL;
+		cifs_dbg(FYI, "unexpected oplock level %d for cached directory\n", oplock);
+		goto oshr_free;
+	}
+
 	smb2_set_next_command(tcon, &rqst[0]);
 
 	memset(&qi_iov, 0, sizeof(qi_iov));
-- 
2.43.0

[PATCH 3/7] cifs: invalidate cfid on unlink/rename/rmdir

[nspmangalore]

From: Shyam Prasad N <sprasad@microsoft.com>

Today we do not invalidate the cached_dirent or the entire
parent cfid when a dentry in a dir has been removed/moved.

This change invalidates the parent cfid so that we don't serve
directory contents from the cache.

Cc: <stable@vger.kernel.org>
Signed-off-by: Shyam Prasad N <sprasad@microsoft.com>
---
 fs/smb/client/inode.c | 40 ++++++++++++++++++++++++++++++++++++++--
 1 file changed, 38 insertions(+), 2 deletions(-)

diff --git a/fs/smb/client/inode.c b/fs/smb/client/inode.c
index 888f9e35f14b8..e077df844c819 100644
--- a/fs/smb/client/inode.c
+++ b/fs/smb/client/inode.c
@@ -28,6 +28,23 @@
 #include "cached_dir.h"
 #include "reparse.h"
 
+static void cifs_invalidate_cached_dir(struct cifs_tcon *tcon,
+				       struct dentry *parent)
+{
+	struct cached_fid *parent_cfid = NULL;
+
+	if (!tcon || !parent)
+		return;
+
+	if (!open_cached_dir_by_dentry(tcon, parent, &parent_cfid)) {
+		mutex_lock(&parent_cfid->dirents.de_mutex);
+		parent_cfid->dirents.is_valid = false;
+		parent_cfid->dirents.is_failed = true;
+		mutex_unlock(&parent_cfid->dirents.de_mutex);
+		close_cached_dir(parent_cfid);
+	}
+}
+
 /*
  * Set parameters for the netfs library
  */
@@ -322,7 +339,7 @@ cifs_unix_basic_to_fattr(struct cifs_fattr *fattr, FILE_UNIX_BASIC_INFO *info,
 				fattr->cf_uid = uid;
 		}
 	}
-	
+
 	fattr->cf_gid = cifs_sb->ctx->linux_gid;
 	if (!(sbflags & CIFS_MOUNT_OVERR_GID)) {
 		u64 id = le64_to_cpu(info->Gid);
@@ -2067,6 +2084,9 @@ static int __cifs_unlink(struct inode *dir, struct dentry *dentry, bool sillyren
 		cifs_set_file_info(inode, attrs, xid, full_path, origattr);
 
 out_reval:
+	if (!rc && dentry->d_parent)
+		cifs_invalidate_cached_dir(tcon, dentry->d_parent);
+
 	if (inode) {
 		cifs_inode = CIFS_I(inode);
 		cifs_inode->time = 0;	/* will force revalidate to get info
@@ -2378,7 +2398,6 @@ int cifs_rmdir(struct inode *inode, struct dentry *direntry)
 	}
 
 	rc = server->ops->rmdir(xid, tcon, full_path, cifs_sb);
-	cifs_put_tlink(tlink);
 
 	cifsInode = CIFS_I(d_inode(direntry));
 
@@ -2388,6 +2407,8 @@ int cifs_rmdir(struct inode *inode, struct dentry *direntry)
 		i_size_write(d_inode(direntry), 0);
 		clear_nlink(d_inode(direntry));
 		spin_unlock(&d_inode(direntry)->i_lock);
+		if (direntry->d_parent)
+			cifs_invalidate_cached_dir(tcon, direntry->d_parent);
 	}
 
 	/* force revalidate to go get info when needed */
@@ -2402,6 +2423,7 @@ int cifs_rmdir(struct inode *inode, struct dentry *direntry)
 
 	inode_set_ctime_current(d_inode(direntry));
 	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
+	cifs_put_tlink(tlink);
 
 rmdir_exit:
 	free_dentry_path(page);
@@ -2501,6 +2523,8 @@ cifs_rename2(struct mnt_idmap *idmap, struct inode *source_dir,
 	struct cifs_sb_info *cifs_sb;
 	struct tcon_link *tlink;
 	struct cifs_tcon *tcon;
+	struct dentry *source_parent;
+	struct dentry *target_parent;
 	bool rehash = false;
 	unsigned int xid;
 	int rc, tmprc;
@@ -2532,6 +2556,8 @@ cifs_rename2(struct mnt_idmap *idmap, struct inode *source_dir,
 	if (IS_ERR(tlink))
 		return PTR_ERR(tlink);
 	tcon = tlink_tcon(tlink);
+	source_parent = source_dentry->d_parent ? dget(source_dentry->d_parent) : NULL;
+	target_parent = target_dentry->d_parent ? dget(target_dentry->d_parent) : NULL;
 	server = tcon->ses->server;
 
 	page1 = alloc_dentry_path();
@@ -2668,11 +2694,21 @@ cifs_rename2(struct mnt_idmap *idmap, struct inode *source_dir,
 	}
 
 	/* force revalidate to go get info when needed */
+	if (!rc) {
+		cifs_invalidate_cached_dir(tcon, source_parent);
+		if (target_parent != source_parent)
+			cifs_invalidate_cached_dir(tcon, target_parent);
+	}
+
 	CIFS_I(source_dir)->time = CIFS_I(target_dir)->time = 0;
 
 cifs_rename_exit:
 	if (rehash)
 		d_rehash(target_dentry);
+	if (target_parent)
+		dput(target_parent);
+	if (source_parent)
+		dput(source_parent);
 	kfree(info_buf_source);
 	free_dentry_path(page2);
 	free_dentry_path(page1);
-- 
2.43.0